Antibiotic Assay Flucytosine
Test Mnemonic
FLCYT
CPT Codes
- 80299 - QTY (1)
LOINC ®
3639-2
Aliases
- 5-Flucytosine
- 5-Fluorocytosine
- Ancobon
- Antimicrobial Assay, 5-Flucytosine
- Fluorocytosine
Performing Laboratory
ARUP
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2 mL | Serum | No additive (Red) | Frozen | Required information: Time and date of collection, time of last dose, and list of all antibiotics that the patient is receiving or has received in the past 48 hours. Aseptically remove 2 mL serum to a sterile aliquot tube and freeze. |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 1 mL |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | 2 hours |
| Refrigerated | 24 hours |
| Frozen | 1 week |
Days Performed
Sun - Sat
Turnaround Time
3 - 4 days
Methodology
| Name | Description |
|---|---|
| Bioassay |
Reference Range
Special Info
Required information: Time and date of collection, time of last dose, and list of all antibiotics that the patient is receiving or has received in the past 48 hours. Plasma is unacceptable. This test is New York DOH approved.
Clinical Info
Normal peak serum concentration for 5-fluorocytosine is 30 - 45 µg/mL with a 2 g PO dose or 60 - 80 µg/mL with a 100 mg/kg/day PO dose. Trough serum concentration is not well established. Toxicity may be seen with sustained levels greater than 100 µg/mL. For bioassay measurements, the presence of other antimicrobial agents may interfere with the assay. Other factors that may influence antimicrobial levels include inherent differences among patients and their underlying physical conditions as well as the dose and route of administration of the antimicrobial agent.